Resolving Classical Experience and the Quantum World.

Explaining the nature of what it is that we can sense and experience of the world outside of ourselves is the primary driver of all our enquiries into the nature of things - that world and the universe that contains it and us. It is crucial to remember here that we are very much a part of the world, it being quite impossible for us to somehow stand outside of it. The stories that we tell each other regarding the things around us, the stories that bind us into cultures and groups, are the source for all the constructions that we develop from our experience, the basis for our sense of ourselves in the world, our sense of purpose and of the spiritual. One set of these stories, and a fundamental one for all of us, is our understanding of the material world, the world that we live in. What is this world that we experience? What is it that we actually do experience? What is the process of that experiencing? How do we understand the range of perceptions that we enact? What is the material, the spiritual? Is there something actually separate that we might call the spiritual or the mental and, ultimately, is there some entity that has overarching responsibility for our being here or did we develop as some sort of function of the universe? These are mightily important stories, for the political consequences of struggles over who has the correct story are at the heart of much of the conflict in the world today.

To those of us in the Western world, the story we tell each other about the material world within which we engage, have our physical being and operate on a daily basis is, in this early 21st century, a story of physics. Developed over the 20th century it has totally broken with the previous stories that our culture produced in the previous several hundred years during which we were doing "science", ie, observing the world to analyse it and discover the rules of its processes. In that earlier period, we felt assured that the world was a solid reliable system with repeatable behaviours. Our assurance of this was the result of much repetition of experiment which gave us the evidence upon which to base this certainty. The things we encountered were distinct, solid, and did not alter in unpredictable ways. But with the beginning of the 20th century certain anomalies, which it had been felt were simply in need of better experiments to resolve, suddenly became major problems because those better experiments showed that in fact the anomalies were not resolvable within the classical paradigm . It turned out that these anomalies could only be adequately explained when one included the idea that the spectrum of light radiated by a heated object was not continuous but came in discrete packets of energy. This was advanced by Planck in his explanation of thermal radiation and sowed the seeds for the development, over the subsequent 25 years, of the concept of the quantum and the discovery of the very strange properties of matter that the quantum theory exposed. Thus began the long period of difficulty in coming to a new stable understanding of the very peculiar behaviour of the world that we have been forced to recognise through quantum physics. 

Schrödinger and Heisenberg independently developed formalisms describing the behaviour of the quantum world in two different mathematical languages. Bohr then showed that these were identical in result and the complete theory of quantum mechanics was established. Nevertheless, the results of experiments based on the theory were deeply troublesome. For example, in the classic double slit experiment with light, photons could readily be shown to be either particles or waves and that these were both perfectly correct results of the experiment depending simply on the kind of experiment carried out. This is the basis for superposition, in which a quantum object (at sub-atomic scale at first, and now also at atomic scale) can behave either as a wave or as a particle. Schrödinger’s wave function formalism of quantum mechanics implies a spreading out (or blurring) of the objects in a system as it evolves. Heisenberg showed that the measurement of what are known as conjugate properties of an object, such as the position and momentum of an electron, were necessarily uncertain if only because the act of measuring one property meant that the conjugate property was perturbed by the very process of measurement of the first. Uncertainty as to the precise position and/or momentum of objects means that they blur over time so that they become non-local or spread out over space and the properties become super(im)posed on each other in that process. As Smolin recently put it, “the properties of any one part of the world are determined by relationships and entanglement with the rest of the world.” [Smolin, 1995]. This is clearly inconsistent with the way things appear in the macroscopic realm. This was very disturbing and continues to be so. Einstein’s oft quoted comment about god not playing dice comes from within the series of debates among physicists that attempted to resolve this problem and others like it. 

This indeterminacy of position and momentum or other conjugate properties, of a system at the microphysical level becomes quite useful, for example, in understanding the cloud of electrons surrounding the nucleus of an atom. But “serious misgivings arise if one notices that the uncertainty affects macroscopically tangible and visible things, for which the term “blurring” seems simply wrong.” [Schrödinger, 1935, p.156] In the case of Schrödinger’s cat which (so far as our knowledge is concerned) may be both alive and dead, “the wave-function of the entire system [has] in it the living and the dead cat mixed or smeared out in equal parts.” [Schrödinger, 1935, p.156] Schrödinger states that the situation is resolved by opening the box and it is his position, in all these situations, that it is the state of our knowledge that is at issue not the state of reality (whatever that may be).  He sums up the situation thus: 

“Reality resists imitation through a model. So one lets go of naïve realism and leans directly on the indubitable proposition that actually (for the physicist) after all is said and done there is only observation, measurement. Then all our physical thinking thenceforth has as sole basis and as sole object the results of measurements which can in principle be carried out, for we must now explicitly not relate our thinking any longer to any other kind of reality or to a model.” [Schrödinger, 1935, p.157]

So, in sum, by inferential processes we have a description of the world which almost beggars description. We know of the world as the world of quantum physics, and as a description of the mechanics of the world it is astonishingly successful. As David Albert comments “… there hasn’t been ever so much as a shred of what you might call normal experimental evidence that the quantum state of any isolated physical system in the world ever fails to evolve in perfect accordance with the linear dynamical equations of motion.” [Albert, 1992, p110-11, his emphasis]. But clearly the nature of the quantum world is not what we experience, descriptions of what we experience indicating solid distinct particulate material that we can touch and manipulate and generally rely on not to behave too oddly. In other words, material that obeys laws grounded in classical physics. There is a perplexing disjunction between the world of our daily experience and the world that we understand through quantum physics. It seems extraordinary that the things we seem to know about the microscopic world, gathered by the demanding and intricate processes of quantum physics, are not in fact things that we can experience of the world, and do not translate up to the scale of the world that we do seem to experience. The two descriptions (classical and quantum) and the worlds they imply are quite incompatible and there appears to be no available bridge between the two. Obviously this cannot be the case when it comes to the actual material that makes up the macroscopic “experiencible” world. The large-scale must be made of the materials described in the small-scale; otherwise everything that we do in our world of, for example, electronic technology would be impossible. As Lockwood remarks regarding Shrödinger’s cat, “given a suitable coupling, any microscopic superposition can be made to generate a corresponding macroscopic one. You cannot, if quantum mechanics is universally applicable, have one without the other. … there is nothing in the character of our ordinary experience that constitutes a shred of evidence that quantum mechanics does in fact break down at the macroscopic level.” [Lockwood, 1989, p.224]

Thus, it remains unclear how physical matter, obeying the "rules" of quantum physics, can be brought into consistency with the clear and distinct experience we have of the macrophysical. One must ask how it could be that the content of an entangled, superposed unitary system, in which the very existence of anything in particular is a function of probabilities, can be clearly resolved into particles and objects by an observer? The disjunction between descriptions of the world affords no adequate bridging theory or explanation, each appears to be quite incompatible with the other. It is this problem that I want to examine and for which I offer the beginnings of a solution. In order to resolve this problem, I will discuss some of the many attempts to re-interpret or add to quantum physics that purport thereby to solve the problem of how the macrophysical comes to manifest. Regarding what are known as “collapse” theories, there is a range of serious objections to the idea of collapse which raise the question of whether the classical world is produced through this process. Likewise with the “no-collapse” theories. Consequently, I argue that there is no need for either such theory in order to produce the “real” world by suggesting a mechanism through which our experience can present us with singular and clear perceptions. 

There are two assumptions, by no means unjustified, upon which the argument to be advanced here rests. The first is that what we know of the world is mediated to us solely through the biology of our sensory systems as experience. All knowledge is, as both Einstein and Bohr took regular pains to emphasise, a matter of instrument readings. What we infer in our sciences are based upon data gained through experience and as such are abstractions from that experience. As Stapp points out “the physical laws represented by quantum theory are not a set of laws governing an independent entity that exists apart from observations. Rather, they define a mathematical structure of statistical relations among observations.” [Stapp, 1993, pp.85-6] This is not to say that the independent entity doesn’t exist but that our knowledge of its behaviour is inferred from our observations only.

The second is that the whole universe is a quantum system having a single integrated wave-function implying that everything in the world is quantum stuff, obeying the rules of quantum mechanics. This includes brains and all manner of biological things as well as the entire inorganic world and the microphysical world of subatomic objects, electrons, photons etc. The basis for this assumption is that given the very long period during which the objects of the universe have been interacting all of them should have become entangled with each other. Looked at from the other direction, given the unitary evolution of the cosmos as a whole from the singularity of the Big Bang everything would have started off as utterly entangled and there are really no means by which any separation could take place.

There is another factor in my argument that I should make clear. This is that I take a physicalist position regarding consciousness, despite the arguments of Chalmers and the many other dualists in philosophical and religious orders. I can only see that consciousness is part and parcel of the organization of the body and brain in its world and in its flow of changes in chemical and neural structure as it operates in that world. Experiencing is a function of brains and their sensory facilities and understanding is a function of the consideration of that experience. Our experience of the world has an informational basis which is built up from the recognition that what we, as biological entities, receive from the world are changes in its physical dynamics. It is the differences in the world that we are able to detect from it. Our sensory systems, in experiencing the world, provoke a cascade of transforms of their input throughout the brain, which, on being integrated up to consciousness, become qualia (the consciously recognised qualities of the matters of our experience), presenting the world as knowable. That is, the basis for any experience and, by extension for qualia in consciousness, is fundamentally physical. It comes from difference relations in the physical world and is mediated into consciousness through the biophysical media of the brain's sensory, feature processing and interpretive structures. What we make of the results of this process are our culture and the framework of our thought. It is a complete reconstruction of the source. The world we know is not and cannot be the world that is there and the problem here becomes the nature of the physical.

Now, physics is a process of making experiments on the world; essentially asking questions of the world and measuring its responses. At the moment of the observation some definite result appears to precipitate from the wave-function of the world. The probabilities of this result are predictable despite the fact that if a different experiment were conducted on the “same” system the results would be quite different. We see this in the classic double-slit experiment. In the “double-slit” experiment with light, a barrier with two slits in it that pass the light, and a measuring apparatus (a photographic plate) are set up as an experimental system and, while both slits are open, the combined influence of the system and the measuring apparatus produce an interference pattern indicating the wave nature of light. If one of the slits is closed, the system then demonstrates the particle nature of photons. As von Neumann noted: “a physical intervention can be nothing else than the temporary insertion of a certain energy coupling into the observed system… [and] … we cannot observe the system S by itself but must rather investigate system S + M in order to obtain (numerically) its interaction with measuring apparatus M.” [von Neumann, 1955, p.352]. This means that the apparatus gathering the data of the experiment is simply carrying on the transforms of its constitution, happily doing its quantum thing. There is no need for a “collapse” event until the experimenter looks at the results on the plate. According to Wigner, von Neumann “postulated that the state vector varies in two different ways. In an isolated (ie, unobserved) system the state vector evolves deterministically – though this evolution includes the presences of orthogonal properties in superposition – but when observed the system changes with a probabilistic nature, jumping discontinuously.” [Wigner, 1983, p.289] Yet, von Neumann could find no point in the experimental system where the observation directly effected the evolution of the state vector. The effect could only be occurring in the “mind” of the observer.

Likewise for our perception of light. The photons are transduced into changes in the pattern of flow of biochemical events across the neural system. All the connections between elements of the network are quantum processes, being the chemically-mediated biological transfer of “information” from one neural layer to the next, right up to the point of recognition in the observer’s “mind”. But all of this, including the evidence on the photographic plate, is quantum stuff and, I argue, continues on as such after any observation. Given the assumption that Shrödinger’s wave-function spreads throughout the universe and is a description of the universe as a single whole system, the universe and everything in it, including us, is made of quantum stuff and the classical cannot possibly actually be there.

Yet, in observing an experiment we make the world, ie, we seem to precipitate from a state of potentiality an actual object separated out from the quantum field and definitely there. But it cannot be so actual. All of the processes of experiencing the world are entirely mediated by quantum processes differentiated as probability densities. At no point in the causal chain can there be said to be an actual world of the kind of objects we so clearly and distinctly perceive and thereby “know” to be there. Nevertheless we get clear and distinct observations from these events. Consequently, the intuitive feeling that what we experience, apparently via the agency of collapse, is in some way actual brings all sorts of difficulties. Thus, the primary problem here is to find a theory of how the world manifests as the discrete deterministic thing that we experience in the face of its utterly counter-intuitive behaviour at the quantum level. 

There are two classes of attempts to interpret quantum mechanics so that we can find a satisfactory understanding of how the experienced world comes to be. The first that I shall deal with are what are known as collapse theories. There is a proliferating variety of these attempts to understand the apparent discontinuity so that we can legitimately have clear and distinct experiences of the macrophysical world. The second class are no-collapse theories in which either something more fundamental than the quantum guides the results or all results occur in parallel but isolated systems (worlds or minds). 

Copenhagen interpretation
The original form of quantum mechanics, as interpreted by Bohr and his colleagues, is that at the moment of the measurement or observation some kind of mysterious process occurs, called the “collapse of the wave function” (if one uses the Schrödinger formalism) or the “reduction of the state vector” (if one uses Heisenberg’s version). This is the Copenhagen Interpretation in which, of the possible alternative results of a measurement, one particular result “precipitates” out, according to some “preferred basis” determined by the measuring apparatus itself (which includes the state of the brain of the observer if that is the measuring apparatus). This event occurs in a jump or discontinuity as it crosses some arbitrary boundary between the unseeable (the microphysical) to the seeable (the macrophysical).

In critically examining this type of “collapse” two questions arise: what is its process and where does it happen in the causal chain? Von Neumann, in his formalization of Quantum Theory [von Neumann, 1955], was unable to determine exactly how and at what moment in an observation or measurement the quantum realm collapses into the classical realm. There is no point in the causal chain of physical or sensory events where this collapse can be detected and thus the putative event must presumably be instantaneous. The idea that collapse is instantaneous cannot hold up within the structure of space-time established in Einstein's relativity theory in that it would be required to happen at, at least, light speed and this requires an  infinity of energy. If it occurs at less than light speed then it would be detectable even if it occurs in the femtosecond range. Consequently he suggested that it must be at the moment when the observation enters consciousness as a perception. 

There is a further problem which is that if there was a time when there were no observers, which given the latency in the evolution of life seems reasonable, then what was the state of the universe before there were observers? It must have existed in a quantum state, but how then did all the physical materials of, say, the solar system come into being so that life (being macrophysical) might evolve. So a dependency on observer or measurement induced collapse has some difficulty getting started, but only if one requires that the world manifest as actual collapsed classical materials.

Decoherence
Another proposal for achieving the manifest world, and this without the problem of the observer, is the decoherence theory developed by Zurek [1998]. It has been widely noted that any attempts to work on a quantum system require that it be exceedingly effectively isolated from the walls of the container or any measuring device lest it interact with that external system and cease to be an example of the process that the experimenter is attempting to work on. That is, as a result of interactions with whatever is around it, the system loses its internal coherence as a quantum system and appears to merge with the state of the surrounding apparatus. This is known as decoherence and is a very real aspect of the difficulties in implementing a so-called quantum computer. Decoherence theory proposes that all quantum systems (apart from the most isolated) in interacting with macrophysical matter must themselves decohere into the macrophysical state. But this requires that there be some sort of collapsed macrophysical environment against which quantum systems might “bump” and thus interact becoming themselves classical. If the universe is a fully quantum universe it is unitary [unified] and cannot actually have any classical manifestation so the likely universality of the wave-function denies the possibility of decoherence. Thus decoherence cannot be a collapse into a macrophysical particulate state, but the re-merging of two quantum systems (and the swamping of one as it “re-coheres” into the larger quantum system of the world). One can think of this objection in another way. If the Universe was born out of the big bang, as seems most likely, then it was born in a singlet state and all further expansion of the universe is a function of the de-localisation of objects which started, and therefore remain, entangled with each other

Stapp's creative acts
Stapp’s proposal for producing collapse supposes that the conscious individual acts in some “creative” process. This creative process amounts to a grasping of one of the possible states in the quantum potentia (at least partly) determined by a history of previous creative acts. For Stapp it involves a conscious act and, as well, produces the states of mind known as qualia (or the feeling of what it is like). Each act of selection precipitates into the manifest world that state which has been selected and somehow all other states evaporate, each act inducing a collapse of the wavefunction of the world at that moment. The mechanism that Stapp proposes involves the neural network of the brain. The “patterns of neural excitations” of the brain’s network evolve according to the dynamics of quantum theory thereby creating in the brain multiple patterns with a range of neural weightings corresponding to the possible states of superpositions of sensory data and current (historically derived) brain states. The brain then selects out one of the patterns by some conscious act [Stapp, 1993, pp.91-4]. But, the problem here is how does the conscious act work? Ie, how does it distinguish among an ensemble of possible states in consciousness when it is the act of selection that must bring only one of those possible states into consciousness. In other words, Stapp has put the cart before the horse, requiring the selection to have been done so that it might then be done in consciousness. There is a way around this, but I will come to it below. Essentially Stapp’s proposal is analogous to von Neumann’s comment that the collapse of the wave function happens at the moment when the observation becomes conscious.

Bohm’s hidden variables
Bohm’s theory proposes that there exist “hidden variables” which somehow act as a deterministic variable more fundamental than the quantum. They cause the universe to evolve according to the Shrödinger equation yet still produce deterministic results, rendering “collapse” unnecessary. Although they are not measurable (remaining outside the realm of experimental testability) their association with the wave function effectively presets the results of an observation to a state determined by the hidden variable. Bohm drew his ideas from de Broglie’s proposal for a “pilot wave”, which somehow knows what the desired outcome is to be, and guides or drives the particle towards that concrete classical state. Either way, one of the elements of the complementary/coupled pair, particle and wave, has an inherent fixity which is carried through to a concrete discrete result on measurement [Bohm, 1952, part II]. There is no experimental evidence for any such system. Moreover, Bell’s inequality shows that there are no possible quantum “objects” which can be in “dispersion free” states, ie, in the discrete or “local” states that Bohm’s hidden variables are supposed to be. [Bell, 1964; Bell, 1966]

In his analysis of Bohm’s “hidden variables” version of quantum mechanics, Bell showed that a measurement of the evolution of one of an entangled pair of photons, or other particulate phenomena, that are separated by some distance is necessarily dependent on the evolution of the other. As Bell put it: “an explicit causal mechanism exists whereby the disposition of one piece of apparatus affects the results obtained with a distant piece” [Bell, 1966, p.402] in a manner that indicates that the two photons cannot be considered as separate. This is non-locality, and implies that over the evolution of the universe, most (if not all) of its “particles” will have interacted and become entangled, and the total wave-function of the universe will not be analysable into a set of independent local wave-functions the properties of which might then be averaged over the whole (as in the statistical mechanics of classical physics). It is probably reasonable to think that this non-locality really means that the wave-function of any thing that we might be tempted to see as an isolated object is in fact smeared out throughout the universe. The well recognised complementarity of states of two entangled but spatially separated entities means simply that they are not two separate entities at all but one single entity in a spatially non-localised state. This was foreshadowed by Schrödinger in 1935: “Any “entanglement of predictions” that takes place can obviously only go back to the fact that the two bodies at some earlier time formed in a true sense one system, that is were interacting, and have left behind traces on each other.” [Schrödinger, 1935, p.161] The state apparently brought on by a measurement of one of the pair can only be complemented by the state of the other. There is no need for super-luminal communication of information and the necessary non-locality clearly calls into question Bohm’s version of quantum mechanics.

Everett’s Relative State Formalism, a.k.a. the Many Worlds theory.
The results of a measurement of an object system can only be known relative to the correlation between the state of the measuring apparatus and the object system. Any sequence of measurements will produce a series of independent results. Thus, in Everett’s formulation, 

“with each succeeding observation (or interaction), the observer state “branches” into a number of different outcomes. Each branch represents a different outcome of the measurement and the corresponding eigenstate for the object-system. All branches exist simultaneously in the superposition after any given sequence of observations.” [Everett, 1957, p.320]. 

“all elements of a superposition (all “branches”) are “actual”, none any more “real” than the rest. It is unnecessary to suppose that all but one are somehow destroyed, since all the separate elements of a superposition individually obey the wave equation with complete indifference to the presence or absence (“actuality” or not) of any other elements. This total lack of effect of one branch on another also implies that no observer will ever be aware of any “splitting process.” [Everett, 1957, p.320 footnote] 

“The fundamental idea of the MWI, going back to Everett 1957, is that there are myriads of worlds in the Universe in addition to the world we are aware of. In particular, every time a quantum experiment with different outcomes with non-zero probability is performed, all outcomes are obtained, each in a different world, even if we are aware only of the world with the outcome we have seen.” [Vaidman, 2002]

Everett’s set of superposed macroscopic systems simply imply that all possible states of the universe are extant, superposed in the one universe, there is no talk of collapse. And his position is little different from the basic version of quantum mechanics, it simply makes explicit what Schrödinger implied in his Cat Paradox [1935] paper, namely that the cat, until such time as an observation is made, exists in a state of being both alive and dead. What Everett does is to draw this universe of superpositions away from being simply a state of our knowledge and points out that it is an actual state of the universe.

Many Minds
Now, Lockwood has developed a version of the relative state hypothesis in which it is states of knowledge that co-exist and that we become conscious of one particular state by some operation of selection via some basis preferred by that consciousness. Lockwood: “What one would normally think of as the state of anything, at a given time, should really be thought of as merely its state relative to the given designated state of oneself” [Lockwood, 1989, p.228] What he has done is to transpose the multiple superposed states of the world in Everett’s formulation, into a series of minds contained in an individual (as a multimind) each of which is perceiving one of the states as its maximal experience. Note that these minds exist quite independently of each other to the point that death might come to one far in advance of the moment that it comes to another. [Lockwood, 1996] The difficulty for me is that each of these minds is a conscious mind and we are presented with an infinity of them all contained in one individual. Apart from the possibility of some sort of schizophrenia (which Lockwood, following Everett, would consider impossible because of the lack of communication between these superposed states) there are just too many minds for my liking, especially as one can do the same job with one conscious mind when one acknowledges that our brains are, like everything else in the universe, part of the entangled non-local quantum system of the universe. And further each of these multiplicities, mind-like or world-like are intended to defeat the non-locality of objects in the universe, and this is just not feasible given Bell’s demonstration of its necessity. 

The upshot of all this, then, is that there really is no way in which a satisfactory interpretation of quantum mechanics can be mounted which supposes that the world actually manifests as the discrete objects of classical physics, the objects that we believe by convention to be there. This must then call into question the nature of our belief itself.

So having taken a critical look at the issue of the manifestation of classical states I must now suggest means by which the fully quantum realm can be perceived clearly and distinctly without this manifestation becoming necessary. 

But first what is the motivation for suggesting any of these interpretations? Do Bohm, Everett, Zurek or any of the others say why they feel the need to propose their theories? Is it to do with the need to have a material world as we believe it to be: an actual out-there in-the-world classical thing, part of that great assumption that the macrophysical world is actually there, as reported in our experience? As the headline in an article referring to a talk by Zurek at the American Association for the Advancement of Science in 1999, says: “Decoherence is our ticket out of the Quantum World” [Zurek, 1999] and it is exactly this issue that produces all this speculation. How do we escape the confusion of superposition and the distributed and uncertain positioning of non-locality of the quantum state of the actual world to get what we consider to be the real? Of course, I am arguing that these additions to physics are mistaken, we cannot escape the quantum world other than through our own perception and the limitations we construct through our selection activity. 

I suggest that the function of these theories of manifestation merely fulfil a psychological need and, in fact, are not necessary.  Suppose that macrophysical manifestation does not occur. Suppose that the world always remains in its fully superposed, entangled, non-local condition and that there is no actualisation of “real” macrophysical objects that we experience from within the framework of a culture based in classical physics. I propose that we leave the mathematical description of the quantum world intact and all its implications regarding superposition and non-locality likewise remain intact. As the engineers say: “if it ain’t broke, don’t fix it” and for all practical purposes quantum mechanics ain’t broke, it’s not even short of funds.

But that means that we have to allow that the whole physical world including conscious brains do their physical business according to the quantum description. That is, all the sensing, feature extraction, integration and control processing systems of the brain are part of the regular quantum system just like everything else. What we then have to do is to explain how the objects of the “experienced” classical world come to be so experienced in human brains. A concept of the brain as a very large highly structured network of neurons will allow us to do this. This is presumably not all the brain is but there are enough similarities to make the neural network a useful metaphor for the discussion to follow.

There is a great range of neuron types but they all have essentially similar structure based on an “input” stage (of tree-like form) referred to as its dendrites, a cell body (presumably in which the main integration of the inputs is done) and an “output” or axon which then synapses onto one or more other neurons usually via their dendritic trees. Networks of neurons throughout the brain have a range and diversity of structures that enable them to handle all the perceptual processes that we need to operate in the world effectively  . From the retina a consistent topography of at least two classes of neurons gives us access to intensity and wavelength information in the spectra of incident photons affording us brightness and colour experience from the world. These retinal neurons enhance their detail in the ganglia behind the retina and then relay to a site on the thalamus in the centre of the brain from whence they are relayed to the visual cortex where a great variety of neural structures extract the features of the world that we have evolved to utilise. From the visual cortex a hugely greater proportion of neurons project back onto the thalamus in forms of feedback which, our best guesses suggest, selectively regulate what we attend to in the first place. This is probably how we operate that ability we have to pay selective attention to some aspect of our world and ignore other aspects unless they themselves force us to shift our attention to them. These chains of neurons may be described as a series of layers analogous to the input, inner (or hidden) and output layers of an artificial neural net, except that here there is a much greater number of inner layers to do all sorts of feature processing and a greater array of connections between layers, with some layers transferring their activation patterns in parallel bifurcations and others in chains. The connections between neurons in these layers are largely chemically mediated synapses of a variety of structures, having excitatory and inhibitory action, transferring signal between the neurons’ axons and dendrites. The synaptic transfer points may be mediated not only by their own neurotransmitters but also by hormonal and other molecules that affect the synaptic transmission in ways that can bring on the slurring of drunkenness or the exquisitely heightened awareness of mescaline. And in the day-to-day they are also deeply influenced by the chemistry of our emotional states. Multiple neurons can synapse onto the next neuron in the chain and multiple synapses from a neuron can add to the connectivity. In several ways the effectiveness of the transfer of activation through a network layer is affected through what is called a weighting. The contribution of one neuron to the next varies depending upon its weights relative to other neurons also synapsing onto that neuron and their proportion of the overall excitatory and inhibitory contributions of all the synapses onto that neuron.

As I understand quantum mechanics, the universe is made up of fields of probability densities that impinge upon the pre-conscious levels of our perceptual systems. In fact, Wigner speaks of probabilities as being the true underlying reality: 

the “probabilities [of the different outcomes] form the real content of quantum mechanical theory. The formalism of state vectors, equations of motion, etc, are only means to calculate these probabilities. The observation results are the true “reality” which underlie quantum mechanics” [Wigner, 1983, p.288].

• must be brought about by the quantum events at our sensory inputs and the behaviour of their neural neighbours, 
• must be within the influence of bio-molecular and other superpositions, 
• must be subject to the blurring (the wholistic influence) of non-locality and spread out as the fields of probability (that I have referred to above). 

Were one to look at the output stages of all the neurons of some particular layer with some kind of remarkable microscope, then one would find what amounts to a surface exhibiting peaks and troughs that map the results of the transform that neural layer has made of its input dataflow. There might be peaks representing  red here and troughs representing blue there corresponding to aspects of some scene under our gaze. Overall this dynamical “surface” will correspond to our construction of the world, but crucially, these states are largely non-overlapping. Where a network has several possible minima, unless the network’s source probabilities are 50-50 (and no history is involved), there will tend to be one minima that is the deepest, corresponding to the probability density with the greatest magnitude. Because one of the attractor basins in this dynamical system will settle to the minimum state it will appear as a clear and distinct object. Thus, we are using the dynamics of the network to distinguish between superposed states. They are clear and distinct because they exist for us as the most likely version of the spectrum of superposed states that our historical network construction will produce. Under certain conditions, for example the Necker-cube illusion, the possible states are identically 50-50 and so as we gaze at the object we are going to flip between the two possible readings of its dataform with only the slightest movement or “noise” triggering the changes of interpretation state. In conscious processing the attractor basins establish qualia as being actual states of the brain. The structure of the history of an entity’s being in the world works as a kind of inertia in the system. It is memory and culture, the framework, forming the accumulated highly differentiated state through which we reconstruct previous experience in our present space.

It will be objected that dynamical systems theories apply only to classical realms in their use of a statistical mechanics to explain the tendency of the system towards a particular state. But it must be remembered that the universe is quantum mechanical and that there are no classical physical versions of the world out there. In fact, I am arguing that they exist only within the consciousness of the observer (as did Bohr, Schrödinger and just about every one else who has written about it, excepting Bohm and Everett). So, we have to suppose that the dynamical systems behaviour of brains and all other complex organised (physical) systems are in fact quantum mechanical even if we find it intractably difficult to describe their behaviour within the quantum mathematics (a là, the many body problem). We also need to keep in mind that we are discussing the state of our knowledge, which is classical. Therefore, a classical dynamical systems approach will have to do.

My version of the situation goes something like this. There is, as described by the Schrödinger equation, a wave-function such that the universe has evolved to include all its superposed states, demonstrates the non-locality described by uncertainty and shown to be necessary by Bell, and does not undergo any type of collapse into classical macrophysical states or branchings into separate worlds. This universe is, then, not what we experience, despite the abstract knowledge we have that allows us to say with some reliability that it is there. What we experience are the states of the universe that we, in bringing experience to consciousness, select from the quantum states of our brains. This selection is made on the basis of the probabilities of those states propagated from the world (the source of the sense data) in conjunction with the “prejudices” imposed by our previous experiences (our histories) on how those sense data are to be interpreted. Complex internally and externally generated states become embedded in the neural structures of our brains and are represented in the dynamics of neural organisation and synaptic weightings in those networks.

The world starts as a “blooming buzzing confusion” and we slowly differentiate it out into distinct and nameable objects as we grow through our experience of it. We are told what things are and those things are presented by the sensory capacities that we have, that make detectable and yet limit what we are actually able to experience in what we are exposed to from the world. We grow in consciousness as we mature physically and the experience we have shapes the long-term inertia of the neural network’s connectionism, while removing us from unmediated knowledge of the world. It may be the plenitude of possibilities that is out there but we build the classical world by our brain’s selection process. The world of Newtonian physics is the world that our qualia have acquired through history and culture. It is the qualia that are the classical, and in a sense, it is consciousness which produces the classical realm.

In his Cat Paradox paper, Schrödinger foreshadowed a view such as that developed here: the object as the result of an observation “is separated out from the entangled knowledge that one has, through an act of perception, which as a matter of fact is not a physical effect on the measured object.” [Schrödinger, 1935, p.162, my emphasis]

Now it appears to me that there is an echo of these characteristics of the quantum world in the attributes of the world described in Buddhist philosophy. Buddhism argues that all that we know are the productions of our minds, constructed from what we have learned to experience through being told what’s what by our parents and others around us. The implication is that the world that is actually there is in itself quite unknowable. This unknowability of the actual and the constructed nature of the phenomenal reminds me explicitly of the void of Buddhist canon. It is said that “The true Buddha is Enlightenment itself”, the Buddha being unknowable while we have any attachment or connectedness with the phenomena of the world [see Conze, 1959]. The constructed world is the primary attachment that we have to break to reach enlightenment, the state of being Buddha. Thus the art of meditation is to stop discriminating, to stop seeing differences in the potentia and simply to see it as one thing, and to see oneself as of that one thing. One must become detached from all discriminations, all constructions, for it is attachment to the products of discrimination, of differentiation, the products of the mind that entrap us in the world. For me the Buddha is that void, the quantum potential, that which is behind everything yet unknowable within our regular sense of “knowing”. But I do disagree with the Buddhist idea of the mind as primary, I want to go further than that and suggest that the mind like all else in the world is made of the same stuff as the physical even though we may not ever be able to tell what that stuff is.

So ultimately we in the west cannot assume that our view of the world is any more correct than any other culture’s view. We have no right to assume that there is a physical manifest world, in fact we may well have to face up to the idea that the eastern view of the world as illusion is more accurate than our traditional view.
 

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